Are You Confident of the Diagnosis?

What you should be alert for in the history

Ganglion cysts are benign, mucin-filled, subcutaneous masses that typically arise from underlying joint capsules, tendons, or tendon sheaths. They represent the most common soft tissue tumors of the hand and digits. Initial patient consultation typically involves a new mass that may be associated with pain, weakness, or unsightly appearance (Figure 1). There is often a concern about malignancy.Prior history of trauma to the area is common.

Figure 1.

A prominent dorsal wrist ganglion cyst.

Ganglion cysts most commonly occur as a single mass in a very specific location, although they have been described in almost all joints of the hand and wrist. They vary in the acuity of presentation, as some appear suddenly and others may gradually enlarge over a period of several months or years. Patients may describe a mass that enlarges with activity and subsides with rest, or a mass that has ruptured or resolved spontaneously.

Characteristic findings on physical examination

History and physical examination are typically sufficient for diagnosis and will reveal a slightly mobile, well-circumscribed, subcutaneous, soft tissue mass that transilluminates and has no overlying skin changes (Figure 2). In dorsal wrist ganglions, pain may be elicited by wrist extension.Aspiration will reveal viscous, mucinous fluid, but is not indicated for routine diagnostic purposes.

Figure 2.

A dorsal wrist ganglion cyst.

Expected results of diagnostic studies

Imaging studies often provide no significant benefit in confirming the diagnosis. Some modalities that have been used include ultrasound, magnetic resonance imaging (MRI), bone scintigraphy, and arthrograms. Radiographs may reveal osteophytic changes of degenerative joint disease in ganglion cysts originating over the distal interphalangeal joint; otherwise, there are no specific findings on x-ray that would confirm the diagnosis. Other imaging modalities are unnecessary in establishing the diagnosis.

Diagnosis confirmation

There is an extensive differential diagnosis for a dorsal wrist mass. A mobile mass that moves with excursion of the extensor tendons may represent a ganglion of the tendon sheath, giant cell tumor of tendon sheath, tenosynovitis of inflammatory or infectious origin, or an extensor digitorum brevis manus muscle belly. The proximal pole of the scaphoid may be prominent dorsally and the proximal pole of the lunate may be prominent volarly. These bony landmarks may be confused with ganglion cysts as these are locations where the cysts are frequently encountered.

An osteophyte from scaphotrapezial arthritis may present as a firm mass that is more radial and slightly more distal than the most commonly presenting site of a dorsal wrist ganglion: the scapholunate articulation.

A venous aneurysm may present as a compressible mass that decreases in size with elevation of the wrist.

Other types of tumors that may mimic ganglions include lipoma, posterior interosseous neuroma, hamartoma, and sarcoma. Careful history and physical examination should reveal the diagnosis in the majority of cases.

Who is at Risk for Developing this Disease?

Ganglion cysts occur three times more commonly in women, and are most prevalent between the second and fourth decades of life; however, they have been described across all age groups, including children. While there is often no clear etiology, major trauma or repetitive minor trauma may be seen in the patient history. Patient occupation has not been demonstrated to correlate with ganglion cyst formation.

What is the Cause of the Disease?

Etiology

There is currently no consensus regarding the pathogenesis of this disease process. Several theories have been proposed over the past 250 years, including synovial herniation, the synovial dermoid theory, and mucoid degeneration. Currently, no single theory adequately explains the spectrum of findings with ganglion cysts. Interestingly, histologic evaluation of ganglion cyst tissue demonstrates a lack of synovial cells or epithelial lining, leading some to argue they are not true cysts.

Pathophysiology

Ganglion cyst fluid has been well described and consists of a clear viscous liquid, containing hyaluronic acid, glucosamine, and albumin.

Systemic Implications and Complications

Ganglion cysts have an association with localized blunt trauma and repetitive minor trauma. Ganglion cysts of the distal interphalangeal joint (digital mucous cysts) are associated with osteoarthritis. Ganglions are otherwise not associated with systemic disorders. Malignant degeneration of ganglion cysts has not been reported.

Treatment Options

Treatment options are summarized in Table I.

Table I.

Treatment options for ganglian cyst.

Nonoperative (for asymptomatic ganglions)

Operative (for symptomatic ganglions)

Observation

Open excision

Aspiration with instillation of a local anesthetic and corticosteroid

Arthroscopic excision

Aspiration alone

Optimal Therapeutic Approach for this Disease

If the diagnosis of ganglion cyst is confirmed and the mass is asymptomatic, then observation is the preferred treatment. Ganglion cysts spontaneously resolve 50% of the time during long-term follow-up; the rate of spontaneous resolution may be higher in children.

Patients often need reassurance that the cyst has no malignant potential. Aspiration is helpful for diagnosis, but not treatment. Aspiration with instillation of local anesthetic and corticosteroid reduces the risk of recurrence when compared to aspiration alone, and can alleviate the discomfort from a symptomatic ganglion. Open surgical excision is the most appropriate treatment for a symptomatic ganglion cyst, and has the lowest recurrence rate of any treatment.

Arthroscopic ganglion cyst excision is an emerging technique that is gaining popularity. Referral to a trained hand surgeon is indicated for surgical intervention.

Patients may inquire about closed rupture, either by firm massage or by striking the cyst with a book, such as a Bible (the source of the historic term “Bible cyst”). This treatment alternative is to be condemned, as it can lead to significant blunt trauma to the hand and wrist.

Patient Management

Patients who present to clinicians with ganglion cysts are frequently concerned with the unpleasant appearance of a mass or the potential for malignancy. Reassurance is the first step in management of these patients.

As ganglion cysts carry no malignant risk and are often asymptomatic, reassurance with follow-up, as needed, is a reasonable approach, with up to 50% patient satisfaction. Definitive intervention is warranted if there are persistent or progressive symptoms and/or patient dissatisfaction with the appearance of these lesions.

Although not successful in the long-term in regards to overall recurrence, aspiration can provide the patient with relief from symptoms and decrease the volume of the cyst to a size that is inconspicuous. Aspiration with instillation of local anesthetic and soluble corticosteroid (5-10mg of dexamethasone mixed with 1% plain lidocaine for a total volume of 3mL) reduces the risk of recurrence, when compared to aspiration alone. Given the poor results and potential harm, instillation of sclerosing agents is not recommended.

Referral to a hand specialist for surgical excision is recommended for symptomatic ganglion cysts. Dorsal wrist ganglions are the most common (60-70%) and typically arise form the scapholunate ligament. Open excision of the cyst, connecting stalk, and an additional cuff of joint capsule results in the lowest risk of recurrence (Figure 3).

Figure 3.

Open excision of a dorsal ganglion cyst.

Volar wrist ganglions are the next most common (18%-20%), and typically arise from the radiocarpal and intercarpal ligaments. Although the excision technique is similar, important structures such as the radial artery are often intimately associated with the stalk and capsule (Figure 4) making aspiration techniques increasingly risky. Wrist immobilization has not been shown to have any benefit in recurrence rates but may provide patient comfort in the early post-operative period.

Figure 4.

Open excision of a volar wrist ganglion cyst.

Ganglion cyst excision is an extremely safe procedure that offers the best chance for cure; it can be done under local anesthesia with very little morbidity and results in few, if any, days of missed work.

Unusual Clinical Scenarios to Consider in Patient Management

Although uncommon, occult ganglion cysts should be suspected with wrist pain of unknown etiology. Physical examination is often inconclusive, and in this instance, Magnetic resonance imaging (MRI), computed tomography (CT), or ultrasound may be useful. Although MRI is the most expensive of the three modalities, it typically generates the most clinically relevant information and can also be diagnostic for many ligamentous, tendinous, and nerve-related disorders.

Peripheral neuropathy associated with ganglion cysts of the wrist, although rare, has been described in the radial sensory, ulnar, and median nerve distributions, and is thought to result from mechanical compression of the nerve by the ganglion cyst. In rare instances, malignant soft tumors of the hand are misdiagnosed as ganglion cysts. If any confusion exists surrounding the diagnosis, prompt referral should be made to a qualified hand specialist.

The condition of multiple ganglion cysts in a single patient has been termed “cystic ganglionosis.” Reports in the literature describe an individual with mulitple ganglion cysts of the wrists and hands, as well as the temporomandibular and atlantoaxial joints.